1. Field of the Invention
The present invention relates to a novel azo dye, a process for making the dye, an ink-jet printing ink using the dye, and an ink-jet recording method.
2. Description of the Related Art
In recent years, the mainstream of new image-recording materials has been materials for forming color images in particular. More specifically, these materials include recording materials based on ink-jet recording, heat-sensitive recording materials based on image transfer, pressure-sensitive recording materials, recording materials based on electronic photography, silver halide photosensitive materials based on transfer, printing inks, and recording pens. Because of inexpensive material costs, capability of high-speed recording, low noise in recording operations, and ease in color recording, ink-jet recording has rapidly come into wide use and is still making further progress. Ink-jet recording methods include a method in which liquid droplets, applied a pressure by a piezoelectric element, are ejected, a method in which liquid droplets are ejected by bubbles generated in the ink by heat, a method in which ultrasonic waves are used, and a method in which liquid droplets are suction-ejected by electrostatic force. In these methods, aqueous ink, oil-based ink, and solid (fusion-type) ink are used.
The properties required for the dye in the ink-jet printing ink are high solubility in a solvent, capability of high-density recording, excellent hue, excellent durability to light, heat, air, water, and chemicals, excellent fixing and little blur on image-receiving materials, excellent storability as ink, freedom from toxicity, high purity, and low cost of production. However, it is very difficult to obtain a dye that highly satisfies these requirements. In particular, there is a strong demand for a dye that has a good magenta hue and exhibits excellent lightfastness. Heretofore, various dyes have been disclosed as pyrazole azo dyes in Japanese Patent Application Laid-Open (JP-A) Nos. 55-161856, 61-36362, 61-152768, 6-145543, and 7-224230, U.S. Pat. Nos. 4,650,861 and 4,301,070, PCT National Publication No. 11-504958 (WO 9634916), and so on. However, none of these dyes meets the requirements of hue and fastness at the same time.
Meanwhile, pyrazole azo dyes were heretofore synthesized according to methods disclosed in U.S. Pat. Nos. 3,336,285 and 3,639,384, U.K. Patent No. 1,566,985, and so on. According to the methods disclosed in the above-mentioned U.S. patents, a 1-alkyl-4-cyano-pyrazole-5-yl azo dye is synthesized via a step of diazotization and subsequent coupling of a 1-alkyl-4-cyano-5-aminopyrazole. However, since the diazonium salt to be formed in the step described above is very unstable, it is difficult to obtain the pyrazole azo dye with good yield and high purity (Weaver and Shuttleworth, Dyes and Pigments 3, 81(1982)). Besides, Japanese Patent Application Publication (JP-B) No. 6-19036 discloses a method of synthesizing a pyrazole azo dye. The l-alkyl-3-(secondary or tertiary alkyl)-4-cyano-pyrazole-5-yl azo dyes obtained by this method have short-wave length hues and a dye satisfactory as a magenta dye has not been obtained.
According to the method disclosed in the above-mentioned U.K. Patent No. 1,566,985, a dye is synthesized by subjecting a l-alkyl-3-alkyl- or aryl-4-cyano-pyrazole-5-yl azo dye and a 1-alkyl-3-alkyl- or aryl-4-halogeno-5-aminopyrazole to diazotization and coupling together with an aromatic coupling component, followed by substituting halogen in a 4-position with cyanide. Since a step of using a heavy metal cyanide such as CuCN or Zn(CN)2 is involved, this method presents problems of waste disposal after use, purification of the dye to be formed, and the like.
It is an object of the present invention to solve the problems described above and to provide a novel azo dye having a good hue and capable of forming images having high lightfastness, an ink-jet printing ink using the dye, and an ink-jet recording method using the ink. Another object of the present invention is to provide a novel manufacturing process enabling production of the azo dye with a high yield. A further object is to provide a novel azo dye which is useful as a water-soluble dye or as a synthesis intermediate for the production of a water-soluble dye and which can become an intermediate of chemicals, drugs, and organic agricultural chemicals.
After close studies of pyrazolyl aniline azo dye derivatives having good hue and high lightfastness, the present inventors found that the above-described problems can be solved by a pyrazole-based azo dye having a specific structure hitherto unknown. Further, after close studies of the manufacturing process of the pyrazole-based azo dye, the present inventors found that the pyrazole-based azo dye can be obtained in a high yield by synthesis via a diazotization step, a coupling step, and an arylation or heterylation step. That is, the above-described objects were achieved by the following means.
A first aspect of the present invention is an azo dye which is represented by general formula (1) or (11) as follows. 
In the general formula (1) and (11), X and X11 represent an electron-withdrawing group having a Hammett""s constant "sgr"p of at least 0.20; R1, R2, R11 and R12 each independently represents a substituted or unsubstituted one of an alkyl group, an alkenyl group, a cycloalkyl group, and an aralkyl group; R3, R4, R5, R6, R13, R14, R15 and R16 each independently represents one of a hydrogen atom, a halogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, an aralkyl group, an aryl group, a heterocyclic group, a cyano group, a hydroxyl group, a nitro group, an amino group, an alkylamino group, an alkoxy group, an aryloxy group, an amido group, an arylamino group, a ureido group, a sulfamoylamino group, an alkylthio group, an arylthio group, an alkoxycarbonylamino group, a sulfonamide group, a carbamoyl group, a sulfamoyl group, a sulfonyl group, an alkoxycarbonyl group, a heterocyclicoxy group, an azo group, an acyloxy group, a carbamoyloxy group, a silyloxy group, an aryloxycarbonyl group, an aryloxycarbonylamino group, an imido group, a heterocyclicthio group, a sulfinyl group, a phosphoryl group, an acyl group, and an ionic hydrophilic group, each of which groups may have at least one of substituent; and each of pair of R1 and R2, R3 and R1, R5 and R2, R11 and R12, R13 and R11, and R15 and R12 may be joined to form a ring; Y represents one of a secondary or tertiary alkyl group and a substituted or unsubstituted aryl group; A represents a group made up of nonmetallic atoms necessary for forming a 5- to 8-membered ring, which ring may have a substituent, may be a saturated ring, and may have an unsaturated bond; Z11 and Z12 each independently represents a halogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, an aralkyl group, an aryl group, a heterocyclic group, a cyano group, a hydroxyl group, a nitro group, an amino group, an alkylamino group, an alkoxy group, an aryloxy group, an amido group, an arylamino group, a ureido group, a sulfamoylamino group, an alkylthio group, an arylthio group, an alkoxycarbonylamino group, a sulfonamide group, a carbamoyl group, a sulfamoyl group, a sulfonyl group, an alkoxycarbonyl group, a heterocyclicoxy group, an azo group, an acyloxy group, a carbamoyloxy group, a silyloxy group, an aryloxycarbonyl group, an aryloxycarbonylamino group, an imido group, a heterocyclicthio group, a sulfinyl group, a phosphoryl group, an acyl group, or an ionic hydrophilic group; and at least one of R11, R12, R13, R14, R15, R16, X11, Y11, Z11, Z12, Z13, Z14, and Z15 represents an ionic hydrophilic group or has an ionic hydrophilic group as a substituent.
A second aspect of the present invention is a process for making an azo dye. The process comprises the steps of:
(a) forming a diazonium salt by reacting an aminopyrazole represented by the general formula (3) as follows: 
with a diazotizing agent;
(b) forming a compound represented by the general formula (5) as follows: 
by reacting the diazonium salt with an aromatic coupling agent represented by the general formula (4) as folloes: 
and;
(c) forming an azo dye represented by the general formula (6) as follows: 
by reacting the compound represented by the general formula (5) with one of an arylating agent and a heterylating agent in the presence of a base. In the general formulas, Xxe2x80x2 represents an electron-withdrawing group having a Hammett""s constant "sgr"p of at least 0.20; R1xe2x80x2 and R2xe2x80x2 each independently represents a substituted or unsubstituted one of an alkyl group, an alkenyl group, a cycloalkyl group, and an aralkyl group; R3xe2x80x2, R4xe2x80x2, Rxe2x80x25 and R6xe2x80x2 each independently represents one of a hydrogen atom, a halogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, an aralkyl group, an aryl group, a heterocyclic group, a cyano group, a hydroxyl group, a nitro group, an amino group, an alkylamino group, an alkoxy group, an aryloxy group, an amido group, an arylamino group, a ureido group, a sulfamoylamino group, an alkylthio group, an arylthio group, an alkoxycarbonylamino group, a sulfonamide group, a carbamoyl group, a sulfamoyl group, a sulfonyl group, an alkoxycarbonyl group, a heterocyclicoxy group, an azo group, an acyloxy group, a carbamoyloxy group, a silyloxy group, an aryloxycarbonyl group, an aryloxycarbonylamino group, an imido group, a heterocyclicthio group, a sulfinyl group, a phosphoryl group, an acyl group, and an ionic hydrophilic group, each of which groups may have at least one of substituent; and each of pair of R1xe2x80x2 and R2xe2x80x2, R3xe2x80x2 and R1xe2x80x2, and R5xe2x80x2 and R2xe2x80x2 may be joined to form a ring; Yxe2x80x2 represents one of a secondary or tertiary alkyl group and a substituted or unsubstituted aryl group; and Axe2x80x2 represents a group made up of nonmetallic atoms necessary for forming a 5- to 8-membered ring, which ring may have a substituent, may be a saturated ring, and may have an unsaturated bond.
A third aspect of the present invention is an ink-jet printing ink containing an azo dye represented by following general formula (1), (10) or (11). 
In the general formula (1) and (11), X and X11 represent an electron-withdrawing group having a Hammett""s constant "sgr"p of at least 0.20; R1, R2, R11 and R12 each independently represents a substituted or unsubstituted one of an alkyl group, an alkenyl group, a cycloalkyl group, and an aralkyl group; R3, R4, R5, R6, R13, R14, R15 and R16 each independently represents one of a hydrogen atom, a halogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, an aralkyl group, an aryl group, a heterocyclic group, a cyano group, a hydroxyl group, a nitro group, an amino group, an alkylamino group, an alkoxy group, an aryloxy group, an amido group, an arylamino group, a ureido group, a sulfamoylamino group, an alkylthio group, an arylthio group, an alkoxycarbonylamino group, a sulfonamide group, a carbamoyl group, a sulfamoyl group, a sulfonyl group, an alkoxycarbonyl group, a heterocyclicoxy group, an azo group, an acyloxy group, a carbamoyloxy group, a silyloxy group, an aryloxycarbonyl group, an aryloxycarbonylamino group, an imido group, a heterocyclicthio group, a sulfinyl group, a phosphoryl group, an acyl group, and an ionic hydrophilic group, each of which groups may have at least one of substituent; and each of pair of R1 and R2, R3 and R1, R5 and R2 R11 and R12, R13 and R11, and R15 and R12 may be joined to form a ring; Y represents one of a secondary or tertiary alkyl group and a substituted or unsubstituted aryl group; A represents a group made up of nonmetallic atoms necessary for forming a 5- to 8-membered ring, which ring may have a substituent, may be a saturated ring, and may have an unsaturated bond; Z11 and Z12 each independently represents a halogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, an aralkyl group, an aryl group, a heterocyclic group, a cyano group, a hydroxyl group, a nitro group, an amino group, an alkylamino group, an alkoxy group, an aryloxy group, an amido group, an arylamino group, a ureido group, a sulfamoylamino group, an alkylthio group, an arylthio group, an alkoxycarbonylamino group, a sulfonamide group, a carbamoyl group, a sulfamoyl group, a sulfonyl group, an alkoxycarbonyl group, a heterocyclicoxy group, an azo group, an acyloxy group, a carbamoyloxy group, a silyloxy group, an aryloxycarbonyl group, an aryloxycarbonylamino group, an imido group, a heterocyclicthio group, a sulfinyl group, a phosphoryl group, an acyl group, or an ionic hydrophilic group; and at least one of R11, R12, R13, R14, R15, R16, X11, Y11, Z11, Z12, Z13, Z14, and Z15 represents an ionic hydrophilic group or has an ionic hydrophilic group as a substituent.
In the general formula (10), X11 represents an electron-withdrawing group having a Hammett""s constant "sgr"p of at least 0.20; R11, R12, R13, R14, R15, R16 and Y11 each independently represents a hydrogen atom, a halogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, an aralkyl group, an aryl group, a heterocyclic group, a cyano group, a hydroxyl group, a nitro group, an amino group, an alkylamino group, an alkoxy group, an aryloxy group, an amido group, an arylamino group, a ureido group, a sulfamoylamino group, an alkylthio group, an arylthio group, an alkoxycarbonylamino group, a sulfonamide group, a carbamoyl group, a sulfamoyl group, a sulfonyl group, an alkoxycarbonyl group, a heterocyclicoxy group, an azo group, an acyloxy group, a carbamoyloxy group, a silyloxy group, an aryloxycarbonyl group, an aryloxycarbonylamino group, an imido group, a heterocyclicthio group, a sulfinyl group, a phosphoryl group, an acyl group, or an ionic hydrophilic group; each of pairs R11 and R12, R13 and R11, and R12 and R15 may be joined to form a ring; A11 represents a group made up of nonmetallic atoms necessary for forming a 5- to 8-membered ring, which may be a saturated ring and may have an unsaturated bond; at least 3 of the nonmetallic atoms in the group represented by A11 are substituted with an N atom of a pyrazole ring, Z11, and Z12, respectively, such that the atom substituted with the N atom of the pyrazole ring is adjacent to both the atom substituted with Z11 and the atom substituted with Z12; Z11 and Z12 each independently represents a halogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, an aralkyl group, an aryl group, a heterocyclic group, a cyano group, a hydroxyl group, a nitro group, an amino group, an alkylamino group, an alkoxy group, an aryloxy group, an amido group, an arylamino group, a ureido group, a sulfamoylamino group, an alkylthio group, an arylthio group, an alkoxycarbonylamino group, a sulfonamide group, a carbamoyl group, a sulfamoyl group, a sulfonyl group, an alkoxycarbonyl group, a heterocyclicoxy group, an azo group, an acyloxy group, a carbamoyloxy group, a silyloxy group, an aryloxycarbonyl group, an aryloxycarbonylamino group, an imido group, a heterocyclicthio group, a sulfinyl group, a phosphoryl group, an acyl group, or an ionic hydrophilic group; and at least one of R11, R12, R13, R14, R15, R16, X11, Y11, Z11, Z12, and A11 represents an ionic hydrophilic group or has an ionic hydrophilic group as a substituent.
The details of the present invention are explained below. First, Hammett""s constant of substitution "sgr"p used herein is explained. Hammett""s rule is an empirical rule proposed by L. P. Hammett in 1935 to quantitatively described the influence of a substituent on reaction or equilibrium of a benzene derivative. Currently, the appropriateness of this rule is widely recognized. "sgr"p and "sgr"m are constants of substitution obtained by Hammett""s rule. These values are described in many common books. For example, details of these values are described in xe2x80x9cLange""s Handbook of Chemistryxe2x80x9d, edited by J. A. Dean, 12 th edition, 1979 (McGraw-Hill), and xe2x80x9cExtra Issue of Kagakuno Ryoikixe2x80x9d, No.122, pp.96-103, 1979 (Nankodo Publishing Co., Ltd.). In the present invention, substituents are defined and explained by Hammett""s constant of substitution "sgr"p. However, it must be noted that substituents are not necessarily limited to substituents for which Hammett""s constants are known and described in these books. Therefore, needless to say, even if a Hammett""s constant of a substituent is not described in these books, a substituent whose Hammett""s constant will fall within a specified range when measured on the basis of Hammett""s rule is included in the scope of the present invention. Although the compounds represented by the general formulaes (1) and (2-1) to (2-9) of the present invention are not benzene derivatives, the values of "sgr"p are used as a scale which shows a electrical effect of substituent, irrespective of the positions of the substitution. In the present invention, values of "sgr"p are used as stated above.
Details of the azo dyes represented by the following general formula (1) of the present invention are given below. 
wherein X represents an electron-withdrawing group having a Hammett""s constant of substitution "sgr"p of 0.20 or greater. Preferably, X is an electron-withdrawing group having a Hammett""s constant "sgr"p of 0.30 or greater and 1.0 or smaller. Specific examples of the electron-withdrawing group having a Hammett""s constant "sgr"p of 0.20 or greater include acyl groups, acyloxy groups, carbamoyl groups, alkyloxycarbonyl groups, aryloxycarbonyl groups, cyano groups, nitro groups, dialkylphosphono groups, diarylphosphono groups, diarylphosphinyl groups, alkylsulfinyl groups, arylsulfinyl groups, alkylsulfonyl groups, arylsulfonyl groups, sulfonyloxy groups, acylthio groups, sulfamoyl groups, thiocyanate groups, thiocarbonyl groups, halogenated alkyl groups, halogenated alkoxy groups, halogenated aryloxy groups, halogenated alkylamino groups, halogenated alkylthio groups, aryl groups substituted with other electron-withdrawing group having up value of 0.20 or greater, heterocyclic groups, halogen atoms, azo groups, and selenocyanate groups.
X may further have a substituent, and examples of such substituent include the following.
A halogen atom (e.g., a chlorine or bromine atom), a straight-chain or branched alkyl group having 1 to 12 carbon atoms, an aralkyl group having 7 to 18 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, a straight-chain or branched alkynyl group having 2 to 12 carbon atoms, a straight-chain or branched cycloalkyl group having 3 to 12 carbon atoms, a straight-chain or branched cycloalkenyl group having 3 to 12 carbon atoms (e.g., methyl, ethyl, propyl, isopropyl, t-butyl, 2-methanesulfonylethyl, 3-phenoxypropyl, trifluoromethyl, or cyclopentyl), an aryl group (e.g., phenyl, 4-t-butylphenyl, or 2,4-di-t-amylphenyl), a heterocyclic group (e.g., imidazolyl, pyrazolyl, triazolyl, 2-furyl, 2-thienyl, 2-pyrimidinyl, or 2-benzotriazolyl), a cyano group, a hydroxyl group, a nitro group, a carboxyl group, an amino group, an alkyloxy group (e.g., methoxy, ethoxy, 2-methoxyethoxy, or 2-methanesulfonylethoxy), an aryloxy group (e.g., phenoxy, 2-methylphenoxy, 4-t-butylphenoxy, 3-nitrophenoxy, 3-t-butyloxycarbamoylphenoxy, or 3-methoxycarbamoyl), an acylamino group (e.g., acetamide, benzamide, or 4-(3-t-butyl-4-hydroxyphenoxy)butaneamide), an alkylamino group (e.g., methylamino, butylamino, diethylamino, or methylbutylamino), an anilino group (e.g., phenylamino or 2-chloroanilino), a ureido group (e.g., phenylureido, methylureido or N,N-dibutylureido), a sulfamoylamino group (e.g., N,N-dipropylsulfamoylamino), an alkylthio group (methylthio, octylthio, or 2-phenoxyethylthio), an arylthio group (e.g., phenylthio, 2-butoxy-5-t-octylphenylthio, or 2-carboxyphenylthio), an alkyloxycarbonylamino group (e.g., methoxycarbonylamino), a sulfonamide group (e.g., methanesulfonamide, benzenesulfoneamide, p-toluenesulfonamide, or octadecanesulfonamide), a carbamoyl group (e.g., N-ethylcarbamoyl or N,N-dibutylcarbamoyl), a sulfamoyl group (e.g., N-ethylsulfamoyl, N,N-dipropylsulfamonyl, or N,N-diethylsulfamoyl), a sulfonyl group (e.g., methanesulfonyl, octanesulfonyl, benzenesulfonyl, or toluenesulfonyl), an alkyloxycarbonyl group (e.g., methoxycarbonyl or butyloxycarbonyl), a heterocyclicoxy group (e.g., 1-phenyltetrazole-5-oxy or 2-tetrahydropyranyloxy), an azo group (e.g., phenylazo, 4-methoxyphenylazo, 4-pivaloylaminophenylazo, or 2-hydroxy-4-propanoylphenylazo), an acyloxy group (e.g., acetoxy), a carbamoyloxy group (e.g., N-methylcarbamoyloxy or N-phenylcarbamoyloxy), a silyloxy group (e.g., trimethylsilyloxy or dibutylmethylsilyloxy), an aryloxycarbonylamino group (e.g., phenoxycarbonylamino), an imide group (e.g., N-succinimide or N-phthalimide), a heterocyclicthio group (e.g., 2-benzothiazolylthio, 2,4-di-phenoxy-1,3,5-triazolei-6-thio, or 2-pyridylthio), a sulfinyl group (e.g., 3-phenoxypropylsulfinyl), a phosphonyl group (e.g., phenoxyphosphonyl, octyloxyphosphonyl, or phenylphosphonyl), an aryloxycarbonyl group (e.g., phenoxycarbonyl), and an acyl group (e.g., acetyl, 3-phenylpropanoyl, or benzoyl).
Preferable examples of X include acyl groups having 2 to 12 carbon atoms, acyloxy groups having 2 to 12 carbon atoms, carbamoyl groups having 1 to 12 carbon atoms, alkyloxycarbonyl groups having 2 to 12 carbon atoms, aryloxycarbonyl groups having 7 to 18 carbon atoms, cyano groups, nitro groups, alkylsulfinyl groups having 1 to 12 carbon atoms, arylsulfinyl groups having 6 to 18 carbon atoms, alkylsulfonyl groups having 1 to 12 carbon atoms, arylsulfonyl groups having 6 to 18 carbon atoms, sulfamoyl groups having 0 to 12 carbon atoms, halogenated alkyl groups having 1 to 12 carbon atoms, halogenated alkyloxy groups having 1 to 12 carbon atoms, halogenated alkylthio groups having 1 to 12 carbon atoms, halogenated aryloxy groups having 7 to 18 carbon atoms, aryl groups which have 7 to 18 carbon atoms and are substituted with 2 or more other electron-withdrawing groups each having a "sgr"p value of 0.20 or greater, and heterocyclic groups which have 1 to 18 carbon atoms and at least one of nitrogen atom, oxygen atom, or sulfur atom.
More preferable examples of X are alkyloxycarbonyl groups having 2 to 12 carbon atoms, nitro groups, cyano groups, alkylsulfonyl groups having 1 to 12 carbon atoms, arylsulfonyl groups having 6 to 18 carbon atoms, carbamoyl groups having 1 to 12 carbon atoms, and halogenated alkyl groups having 1 to 12 carbon atoms. Particularly preferable examples of X are cyano groups, alkylsulfonyl groups having 1 to 12 carbon atoms, and arylsulfonyl groups having 6 to 18 carbon atoms. The most preferable examples of X are cyano groups.
In the general formula (1), R1 and R2 each independently represents a substituted or unsubstituted alkyl group, cycloalkyl group, aralkyl group, or alkenyl group.
Examples of alkyl groups represented by R1 and R2 include alkyl groups having one or more substituents, and unsubstituted alkyl groups. Preferably, the alkyl groups are alkyl groups having 1 to 12 carbon atoms. More preferably, the alkyl groups are alkyl groups having 1 to 6 carbon atoms. Examples of the substituent include a hydroxyl group, an alkoxy group, an alkoxycarbonyl group, a cyano group, a halogen atom, and an ionic hydrophilic group. Examples of the alkyl group include methyl, ethyl, butyl, isopropyl, t-butyl, hydroxyethyl, methoxyethyl, cyanoethyl, trifluoromethyl, 3-sulfopropyl, and 4-sulfobutyl.
Examples of cycloalkyl groups represented by R1 and R2 include cycloalkyl groups having one or more substituents, and unsubstituted cycloalkyl groups. The cycloalkyl groups are preferably cycloalkyl groups having 5 to 12 carbon atoms. Examples of the substituent include an ionic hydrophilic group. Examples of the cycloalkyl groups include a cyclohexyl group.
Examples of aralkyl groups represented by R1 and R2 include aralkyl groups having one or more substituents, and unsubstituted aralkyl groups. The aralkyl groups are preferably aralkyl groups having 7 to 12 carbon atoms. Examples of the substituent include an ionic hydrophilic group. Examples of the aralkyl groups include a benzyl group and a 2-phenethyl group.
Examples of alkenyl groups represented by R1 and R2 include alkenyl groups having one or more substituents, and unsubstituted alkenyl groups. The alkenyl groups are preferably alkenyl groups having 5 to 12 carbon atoms. Examples of the substituent include an ionic hydrophilic group. Examples of the alkenyl groups include a vinyl group and an allyl group.
R3, R4, R5 and R6 each independently represents a hydrogen atom, a halogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, an aralkyl group, an aryl group, a heterocyclic group, a cyano group, a hydroxyl group, a nitro group, an amino group, an alkylamino group, an alkoxy group, an aryloxy group, an amido group, an arylamino group, a ureido group, a sulfamoylamino group, an alkylthio group, an arylthio group, an alkoxycarbonylamino group, a sulfonamide group, a carbamoyl group, a sulfamoyl group, a sulfonyl group, an alkoxycarbonyl group, a heterocyclicoxy group, an azo group, an acyloxy group, a carbamoyloxy group, a silyloxy group, an aryloxycarbonyl group, an aryloxycarbonylamino group, an imido group, a heterocyclicthio group, a sulfinyl group, a phosphoryl group, an acyl group, or an ionic hydrophilic group.
Of the groups listed above, R3, R4, R5 and R6 are preferably a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a cyano group, an alkoxy group, an amido group, a ureido group, an alkoxycarbonylamino group, a sulfonamide group, a carbamoyl group, a sulfamoyl group, or an alkoxycarbonyl group. R3, R4, R5 and R6 are more preferably a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an amido group, a ureido group, a sulfonamide group, a carbamoyl group, or a sulfamoyl group.
The halogen atoms represented by R3, R4, R5 and R6 include a fluorine atom, a chlorine atom, and a bromine atom.
Alkyl groups represented by R3, R4, R5 and R6 include alkyl groups having one or more substituents, and unsubstituted alkyl groups. Preferably, the alkyl groups are alkyl groups having 1 to 12 carbon atoms. Examples of the substituent include a hydroxyl group, an alkoxy group, a cyano group, a halogen atom, and an ionic hydrophilic group. Examples of the alkyl group include methyl, ethyl, butyl, isopropyl, t-butyl, hydroxyethyl, methoxyethyl, cyanoethyl, trifluoromethyl, 3-sulfopropyl, and 4-sulfobutyl.
Cycloalkyl groups represented by R3, R4, R5 and R6 include cycloalkyl groups having one or more substituents, and unsubstituted cycloalkyl groups. The cycloalkyl groups are preferably cycloalkyl groups having 5 to 12 carbon atoms. Examples of the substituent include an ionic hydrophilic group. Examples of the cycloalkyl groups include a cyclohexyl group.
Aralkyl groups represented by R3, R4, R5 and R6 include aralkyl groups having one or more substituents, and unsubstituted aralkyl groups. The aralkyl groups are preferably aralkyl groups having 7 to 12 carbon atoms. Examples of the substituents include an ionic hydrophilic group. Examples of the aralkyl groups include a benzyl group and a 2-phenethyl group.
Aryl groups represented by R3, R4, R5 and R6 include aryl groups having one or more substituents, and unsubstituted aryl groups. The aryl groups are preferably aryl groups having 7 to 12 carbon atoms. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, an alkylamino group, and an ionic hydrophilic group. Examples of the aryl groups include phenyl, p-tolyl, p-methoxyphenyl, o-chlorophenyl, and m-(3-sulfopropylamino)phenyl.
Heterocyclic groups represented by R3, R4, R5 and R6 include heterocyclic groups having one or more substituents, and unsubstituted heterocyclic groups. The heterocyclic groups are preferably 5- or 6-membered heterocyclic groups. Examples of the substituent include an ionic hydrophilic group. Examples of the heterocyclic groups include a 2-pyridyl group, a 2-thienyl group, and a 2-furyl group.
Alkylamino groups represented by R3, R4, R5 and R6 include alkylamino groups having one or more substituents, and unsubstituted alkylamino groups. The alkylamino groups are preferably alkylamino groups having 1 to 6 carbon atoms. Examples of the substituent include an ionic hydrophilic group. Examples of the alkylamino groups include a methylamino group and a diethylamino group.
Alkoxy groups represented by R3, R4, R5 and R6 include alkoxy groups having one or more substituents, and unsubstituted alkoxy groups. The alkoxy groups are preferably alkoxy groups having 1 to 12 carbon atoms. Examples of the substituent include an alkoxy group, a hydroxyethyl group, and an ionic hydrophilic group. Examples of the alkoxy groups include a methoxy group, an ethoxy group, an isopropoxy group, a methoxyethoxy group, a hydroxyethoxy group, and a 3-carboxypropoxy group.
Aryloxy groups represented by R3, R4, R5 and R6 include aryloxy groups having one or more substituents, and unsubstituted aryloxy groups. The aryloxy groups are preferably aryloxy groups having 6 to 12 carbon atoms. Examples of the substituent include an alkoxy group and an ionic hydrophilic group. Examples of the aryloxy groups include a phenoxy group, a p-methoxyphenoxy group, and an o-methoxyphenoxy group.
Amido groups represented by R3, R4, R5 and R6 include amido groups having one or more substituents, and unsubstituted amido groups. The amido groups are preferably amido groups having 2 to 12 carbon atoms. Examples of the substituent include an ionic hydrophilic group. Examples of the amido groups include an acetamide group, a propionamide group, a benzamide group, and a 3,5-disulfobenzamide group.
Arylamino groups represented by R3, R4, R5 and R6 include arylamino groups having one or more substituent, and unsubstituted arylamino groups. The arylamino groups are preferably arylamino groups having 6 to 12 carbon atoms. Examples of the substituents include a halogen atom and an ionic hydrophilic group. Examples of the arylamino groups include an anilino group and a 2-chloroanilino group.
Ureido groups represented by R3, R4, R5 and R6 include ureido groups having one or more substituents, and unsubstituted ureido groups. The ureido groups are preferably ureido groups having 1 to 12 carbon atoms. Examples of the substituent include an alkyl group and an aryl group. Examples of the ureido groups include a 3-methylureido group, a 3,3-dimethylureido group, and a 3-phenylureido group.
Sulfamoylamino groups represented by R3, R4, R5 and R6 include sulfamoylamino groups having one or more substituents, and unsubstituted sulfamoylamino groups. Examples of the substituent include an alkyl group. Examples of the sulfamoylamino groups include an N,N-dipropylsulfamoylamino group.
Alkylthio groups represented by R3, R4, R5 and R6 include alkylthio groups having one or more substituents, and unsubstituted alkylthio groups. The alkylthio groups are preferably alkylthio groups having 1 to 12 carbon atoms. Examples of the substituent include an ionic hydrophilic group. Examples of the alkylthio groups include a methylthio group and an ethylthio group.
Arylthio groups represented by R3, R4, R5 and R6 include arylthio groups having one or more substituents, and unsubstituted arylthio groups. The arylthio groups are preferably arylthio groups having 6 to 12 carbon atoms. Examples of the substituent include an alkyl group and an ionic hydrophilic group. Examples of the arylthio groups include a phenylthio group and a p-tolylthio group.
Alkoxycarbonylamino groups represented by R3, R4, R5 and R6 include alkoxycarbonylamino groups having one or more substituents, and unsubstituted alkoxycarbonylamino groups. The alkoxycarbonylamino groups are preferably alkoxycarbonylamino groups having 2 to 12 carbon atoms. Examples of the substituent include an ionic hydrophilic group. Examples of the alkoxycarbonylamino groups include an ethoxycarbonylamino group.
Sulfonamide groups represented by R3, R4, R5 and R6 include sulfonamide groups having one or more substituents, and unsubstituted sulfonamide groups. The sulfonamide groups are preferably sulfonamide groups having 1 to 12 carbon atoms. Examples of the substituent include an ionic hydrophilic group. Examples of the sulfonamide groups include a methanesulfonamide group, a benzenesulfonamide group, and a 3-carboxybenzenesulfonamide group.
Carbamoyl groups represented by R3, R4, R5 and R6 include carbamoyl groups having one or more substituents, and unsubstituted carbamoyl groups. Examples of the substituent include an alkyl group. Examples of the carbamoyl groups include a methylcarbamoyl group and a dimethylcarbamoyl group.
Sulfamoyl groups represented by R3, R4, R5 and R6 include sulfamoyl groups having one or more substituents, and unsubstituted sulfamoyl groups. Examples of the substituent include an alkyl group. Examples of the sulfamoyl groups include a dimethylsulfamoyl group and a di-(2-hydroxyethyl)sulfamoyl group.
Sulfonyl groups represented by R3, R4, R5 and R6 include a methanesulfonyl group and a phenylsulfonyl group.
Alkoxycarbonyl groups represented by R3, R4, R5 and R6 include alkoxycarbonyl groups having one or more substituents, and unsubstituted alkoxycarbonyl groups. The alkoxycarbonyl groups are preferably alkoxycarbonyl groups having 2 to 12 carbon atoms. Examples of the substituent include an ionic hydrophilic group. Examples of the alkoxycarbonyl groups include a methoxycarbonyl group and an ethoxycarbonyl group.
Heterocyclicoxy groups represented by R3, R4, R5 and R6 include heterocyclicoxy groups having one or more substituents, and unsubstituted heterocyclicoxy groups. The heterocyclicoxy groups are preferably heterocyclicoxy groups having a 5- or 6-membered heterocycle. Examples of the substituent include a hydroxyl group and an ionic hydrophilic group. Examples of the heterocyclicoxy groups include a 2-tetrahydropyranyloxy group.
Azo groups represented by R3, R4, R5 and R6 include azo groups having one or more substituents, and unsubstituted azo groups. Examples of the azo groups include a p-nitrophenyl azo group.
Acyloxy groups represented by R3, R4, R5 and R6 include acyloxy groups having one or more substituents, and unsubstituted acyloxy groups. The acyloxy groups are preferably acyloxy groups having 1 to 12 carbon atoms. Examples of the substituent include an ionic hydrophilic group. Examples of the acyloxy groups include an acetoxy group and a benzoyloxy group.
Carbamoyloxy groups represented by R3, R4, R5 and R6 include carbamoyloxy groups having one or more substituents, and unsubstituted carbamoyloxy groups. Examples of the substituent include an alkyl group. Examples of the carbamoyloxy groups include an N-methylcarbamoyloxy group.
Silyloxy groups represented by R3, R4, R5 and R6 include silyloxy groups having one or more substituents, and unsubstituted silyloxy groups. Examples of the substituent include an alkyl group. Examples of the silyloxy groups include a trimethylsilyloxy group.
Aryloxycarbonyl groups represented by R3, R4, R5 and R6 include aryloxycarbonyl groups having one or more substituents, and unsubstituted aryloxycarbonyl groups. The aryloxycarbonyl groups are preferably aryloxycarbonyl groups having 7 to 12 carbon atoms. Examples of the substituent include an ionic hydrophilic group. Examples of the aryloxycarbonyl groups include a phenoxycarbonyl group.
Aryloxycarbonylamino groups represented by R3, R4, R5 and R6 include aryloxycarbonylamino groups having one or more substituents, and unsubstituted aryloxycarbonylamino groups. The aryloxycarbonylamino groups are preferably aryloxycarbonylamino groups having 7 to 12 carbon atoms. Examples of the substituent include an ionic hydrophilic group. Examples of the aryloxycarbonylamino groups include a phenoxycarbonylamino group.
Imido groups represented by R3, R4, R5 and R6 include imido groups having one or more substituents, and unsubstituted imido groups. Examples of the imido groups include an N-phthalimido group and an N-succinimido group.
Heterocyclicthio groups represented by R3, R4, R5 and R6 include heterocyclicthio groups having one or more substituents, and unsubstituted heterocyclicthio groups. The heterocyclicthio groups preferably have a 5- or 6-membered heterocycle. Examples of the substituent include an ionic hydrophilic group. Examples of the heterocyclicthio groups include a 2-pyridylthio group.
Sulfinyl groups represented by R3, R4, R5 and R6 include sulfinyl groups having one or more substituents, and unsubstituted sulfinyl groups. Examples of the sulfinyl groups include a phenylsulfinyl group.
Phosphoryl groups represented by R3, R4, R5 and R6 include phosphoryl groups having one or more substituents, and unsubstituted phosphoryl groups. Examples of the phosphoryl groups include a phenoxyphosphoryl group and a phenylphosphoryl group.
Acyl groups represented by R3, R4, R5 and R6 include acyl groups having one or more substituents, and unsubstituted acyl groups. The acyl groups are preferably acyl groups having 1 to 12 carbon atoms. Examples of the substituent include an ionic hydrophilic group. Examples of the acyl groups include an acetyl group and a benzoyl group.
Ionic hydrophilic groups represented by R3, R4, R5 and R6 include a carboxyl group, a sulfo group, and a quaternary ammonium group. The ionic hydrophilic groups are preferably a carboxyl group and a sulfo group and particularly preferably a sulfo group. The carboxyl group and sulfo group may each be in a state of a salt. Examples of a counter ion that forms the salt include alkali metal ions (e.g., a sodium ion or a potassium ion) and organic cations (e.g., tetramethylguanidinium ion).
In the general formula (1), R1 and R2, R3 and R1, and R5 and R2 may each form a ring. Where the ring is formed, preferable examples of the ring are as given below. 
In the general formula (1), Y represents a secondary or tertiary alkyl group or, alternatively, a substituted or unsubstituted aryl group. Y is preferably a secondary or tertiary alkyl group and more preferably a tertiary alkyl group. Specific examples thereof include an isopropyl group, a t-butyl group, and an aryl group. These substituents may be further substituted with such substituents as a hydroxyl group, an alkoxy group, a cyano group, alkyl group, a sulfamoyl group, an amido group, a carbamoyl group, a halogen atom, or an ionic hydrophilic group.
In the general formula (1), A represents a group made up of nonmetallic atoms necessary for forming a 5- to 8-membered ring. This ring may have a substituent. Further, this ring may be a saturated ring or may have an unsaturated bond. Preferable examples of the nonmetallic atoms include a nitrogen atom, an oxygen atom, a sulfur atom, and a carbon atom.
Examples of A include a benzene ring, a cyclopentane ring, a cyclohexane ring, a cycloheptane ring, a cyclooctane ring, a cyclohexene ring, a pyridine ring, a piperazine ring, an oxane ring, and a thiane ring. When these rings further have a substituent, examples of the substituent include those listed above as examples of the substituents R3. R4, R5 and R6.
Preferably, A is any one of the groups represented by the following general formulae (2-1) to (2-9). 
In the formulae described above, Z1 and Z2 each independently represents a halogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, an aralkyl group, an aryl group, a heterocyclic group, a cyano group, a hydroxyl group, a nitro group, an amino group, an alkylamino group, an alkoxy group, an aryloxy group, an amido group, an arylamino group, a ureido group, a sulfamoylamino group, an alkylthio group, an arylthio group, an alkoxycarbonylamino group, a sulfonamide group, a carbamoyl group, a sulfamoyl group, a sulfonyl group, an alkoxycarbonyl group, a heterocyclicoxy group, an azo group, an acyloxy group, a carbamoyloxy group, a silyloxy group, an aryloxycarbonyl group, an aryloxycarbonylamino group, an imido group, a heterocyclicthio group, a sulfinyl group, a phosphoryl group, an acyl group, or an ionic hydrophilic group. In the formulae described above, Z3, Z4, Z5, Z7, Z8, Z10, Z11, Z12, Z13, Z14, Z15, Z16, Z17, Z18, Z19,Z20, Z21, Z22,Z23, Z24, Z25, and Z26 each independently represents a hydrogen atom, a halogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, an aralkyl group, an aryl group, a heterocyclic group, a cyano group, a hydroxyl group, a nitro group, an amino group, an alkylamino group, an alkoxy group, an aryloxy group, an amido group, an arylamino group, a ureido group, a sulfamoylamino group, an alkylthio group, an arylthio group, an alkoxycarbonylamino group, a sulfonamide group, a carbamoyl group, a sulfamoyl group, a sulfonyl group, an alkoxycarbonyl group, a heterocyclicoxy group, an azo group, an acyloxy group, a carbamoyloxy group, a silyloxy group, an aryloxycarbonyl group, an aryloxycarbonylamino group, an imido group, a heterocyclicthio group, a sulfinyl group, a phosphoryl group, an acyl group, or an ionic hydrophilic group.
Z6 and Z9 each independently represents Nxe2x80x94R, an oxygen atom, or a sulfur atom. R has the same meaning as Z3, Z4 and Z5.
In the general formula (2-1), specific examples of the groups represented by Z1, Z2, Z3, Z4, and Z5 include the groups listed as specific examples of the groups represented by the substituents R3, R4, R5, and R6 in the general formula (1).
In the general formula (2-1), preferably, Z1 and Z2 are each a halogen atom, an alkyl group, an aryl group, a cyano group, a nitro group, an alkoxy group, an amido group, a ureido group, a sulfamoylamino group, an alkoxycarbonylamino group, a sulfonamide group, a carbamoyl group, a sulfamoyl group, a sulfonyl group, an alkoxycarbonyl group, an acyloxy group, a carbamoyloxy group, an imido group, a sulfinyl group, a phosphoryl group, an acyl group, or an ionic hydrophilic group.
In the general formula (2-1), preferably, Z3, Z4 and Z5 are each a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a cyano group, a nitro group, an alkoxy group, an amido group, a ureido group, a sulfamoylamino group, an alkoxycarbonylamino group, a sulfonamide group, a carbamoyl group, a sulfamoyl group, a sulfonyl group, an alkoxycarbonyl group, an acyloxy group, a carbamoyloxy group, an imido group, a sulfinyl group, a phosphoryl group, an acyl group, or an ionic hydrophilic group.
Further, in the general formula (2-1), preferably at least two of Z1, Z2, Z3, Z4 and Z5 are substituted with substituents whose sum of the values of "sgr"p is 0.4 or greater.
In the general formula (2-1), preferably, Z1 and Z2 are each independently a halogen atom, a cyano group, a nitro group, an alkoxy group, an amido group, a ureido group, a sulfamoylamino group, an alkoxycarbonylamino group, a sulfonamide group, a sulfonyl group, or an ionic hydrophilic group; more preferably, Z3, Z4 and Z5 are each independently a hydrogen atom, a halogen atom, a cyano group, a nitro group, an alkoxy group, an amido group, a ureido group, a sulfamoylamino group, an alkoxycarbonylamino group, a sulfonamide group, a sulfonyl group, or an ionic hydrophilic group; and most preferably, at least two of Z1, Z2, Z3, Z4 and Z5 are substituted with substituents whose sum of the values of "sgr"p is 0.4 or greater.
In the general formulae (2-3) to (2-9), specific examples of the groups represented by Z7, Z8, Z10, Z11, Z12, Z13, Z14, Z15, Z16, Z17, Z18, Z19, Z20, Z21, Z22, Z23, Z24, Z25, and Z26 include the groups listed as the specific examples of the groups represented by the substituents R3, R4, R5, and R6 in the general formula (1). In particular, preferably, Z7, Z8, Z10, Z11, Z12, Z13, Z14, Z15, Z16, Z17 Z18, Z19, Z20, Z21, Z22, Z23, Z24, Z25, and Z26 are each a hydrogen atom, a halogen atom, an alkyl group, a cyano group, a nitro group, an alkoxy group, an amido group, a ureido group, a sulfamoylamino group, an alkoxycarbonylamino group, a sulfonamide group, a carbamoyl group, a sulfamoyl group, a sulfonyl group, an alkoxycarbonyl group, an acyloxy group, a carbamoyloxy group, an imido group, a sulfinyl group, a phosphoryl group, an acyl group, or an ionic hydrophilic group.
More preferably, Z7, Z8, Z10, Z11, Z12, Z13, Z14, Z15, Z16, Z17, Z18, Z19, Z20, Z21, Z22, Z23, Z24 Z25, and Z26 are each a hydrogen atom, a halogen atom, a cyano group, a nitro group, an alkoxy group, an amido group, a ureido group, a sulfamoylamino group, an alkoxycarbonylamino group, a sulfonamide group, a sulfonyl group, or an ionic hydrophilic group.
The preferable scope of the azo dyes represented by the general formula (1) are the azo dyes represented by any one of the following general formulae (7-1) to (7-9). The groups in the following general formulae (7-1) to (7-9) have the same respective meanings as the groups, in the general formula (1) and the general formulae (2-1) to (2-9). 
Of the azo dyes represented by the general formula (1) the most preferable combination of substituents is as follows. X is a cyano group, an alkylsulfonyl group having 1 to 12 carbon atoms, or an arylsulfonyl group having 6 to 18 carbon atoms, and is most preferably a cyano group; Y is a secondary or tertiary alkyl or aryl group, and is most preferably a t-butyl group; R1 and R2 are each independently an alkyl group (which may have an ionic hydrophilic group as a substituent); R6 is an amido group, a ureido group, a sulfamoylamino group, an alkoxycarbonylamino group, or a sulfonamide group, and is most preferably an amido group, a ureido group, or a sulfonamide group (which may have an ionic hydrophilic group as a substituent); Z1 and Z2 are each independently a halogen atom or an alkyl group; and Z4 is a hydrogen atom, a halogen atom, an amido group, a sulfonamide group, a carbamoyl group, a sulfamoyl group, an alkoxycarbonyl group or an ionic hydrophilic group, and is most preferably an amido group.
Specific examples of the azo dyes (indicated as exemplary compounds 1-1 to 1-36) are given below. However, it should be noted that the present invention is not limited to these specific examples. 
Next, the process for making the azo dyes of the present invention is explained in detail below.
The process for making the azo dyes of the present invention has (a) a step in which a diazonium salt is formed by a reaction between an aminopyrazole represented by a general formula (3) and a diazotizing agent, (b) a step in which an azo dye represented by a general formula (5) is formed by a reaction between the diazonium salt and an aromatic coupling agent represented by a general formula (4), and (c) a step in which an azo dye represented by a general formula (6) is formed by the reaction between the azo dye represented by the general formula (5) and an arylating agent or a heterylating agent in the presence of a base.
Further, after the step (c), a step in which a substituent is introduced into Axe2x80x2 by using a suitable reagent may be added. 
In the general formulae described above, Xxe2x80x2, Yxe2x80x2, Rxe2x80x21, Rxe2x80x22, Rxe2x80x23, Rxe2x80x24, Rxe2x80x25, Rxe2x80x26 and Axe2x80x2 have the same respective meanings as X, Y, R1, R2, R3, R4, R5, R6 and A in the general formula (1).
By carrying out the steps (a) to (c), a pyrazole azo dye (e.g., a 1-aryl- or heteryl-3-secondary or tertiary alkyl-4-cyano-pyrazole-5-yl azo dye or a 1-aryl- or heteryl-3-aryl-4-cyano-pyrazole-5-yl azo dye) represented by the general formula (5) can be synthesized as a high-purity product with a good yield. If a pyrazole azo dye which is obtained without carrying out the steps (a) to (c), such as a dye having no secondary or tertiary alkyl or aryl in a 3-position (e.g., a 4-cyano-pyrazolyl azo dye), was alkylated, a mixture of a pyrazole-3-yl azo dye and a pyrazole-5-yl azo dye would be formed. Since hue of the pyrazole-3-yl azo dye is different from a desired hue of the pyrazole-5-yl azo dye (i.e., the pyrazole-3-yl azo dye absorbs light having lower wavelengths), these dyes would need to be separated from each other so as to obtain the desired hue, but separation is difficult. However, if a pyrazole azo dye is prepared by carrying out the steps (a) to (c), the above-described disadvantage does not occur because the pyrazole-3-yl azo dye is not formed. On the other hand, if a pyrazole azo dye (e.g., a 1,3-dialkyl or 1-alkyl-3-aryl-4-cyano-pyrazole-5-yl azo dye) was synthesized by direct diazotization of a corresponding aminopyrazole (e.g., a 1-alkyl-3-aryl-4-cyano-5-aminopyrazole), the yield would be so low that this synthetic process cannot be practically used. In addition, the structure of an alkylhydrazine that is a raw material necessary for synthesis of the aminopyrazole (e.g., 1-alkyl-4-cyano-5-aminopyrazole) is limited and the synthesis of such alkylhydrazine is often difficult. According to the process of the present invention, the above-mentioned raw material is not necessary and the azo dyes can be produced in a stable manner and in a high yield.
The diazotizing agent that is used in the step (a) is preferably sodium nitrite dissolved in a dilute aqueous hydrochloric acid solution. In addition, isopentyl nitrite or nitrosyl sulfuric acid in trifluoroacetic acid can also be used as the diazotizing agent.
The aromatic coupling agent that is used in the step (b) is preferably a 3-acetamide-N,N-dialkylaniline.
Examples of the arylating agent or heterylating agent that is used in the step (c) include the compounds represented by the following general formulae (8-1) to (8-9). 
Zxe2x80x31 to Zxe2x80x326 in the general formulae (8-1) to (8-9) have the same respective meanings as Z1 to Z26 in the general formulae (2-1) to (2-9). It is preferable that Zxe2x80x31 to Zxe2x80x35 are substituted with substituents whose sum of the Hammett constants "sgr"p is 0.15 or greater or that Zxe2x80x34 is a nitro group. C represents a halogen atom or xe2x80x94OSO2Rxe2x80x2. Rxe2x80x2 represents an alkyl group or aryl group such as an a phenyl group.
Examples of the base that is used in the step (C) include organic bases such as tetrabutylammonium hydroxide and diisopropylethylamine; and inorganic bases such as potassium carbonate, sodium carbonate, sodium hydrogencarbonate, potassium hydrogencarbonate, sodium hydroxide, and potassium hydroxide.
An example of reaction formulae of the process described previously is given below. 
In the formulae, B represents t-butyl, isopropyl, phenyl, or the like; E represents substituted aminophenyl, tetrahydroquinolyl, julolidinyl, or the like; and G represents a hydrogen atom that can be replaced with a diazonium salt.
The starting materials represented by the general formula (3) to be used in the process (particularly secondary or tertiary alkyl-4-cyano-5-aminopyrazole and 3-aryl-4-cyano-5-aminopyrazole in the reaction formulae described above) can be synthesized by the processes described in U.S. Pat. No. 3,336,285, xe2x80x9cHeterocyclesxe2x80x9d, 20, 519(1983), and JP-B No. 6-19036.
The exemplary compounds 1-1 to 1-36 can be prepared by the process of the present invention.
Next, azo dyes represented by the following general formula (10) are described in detail. 
In the general formula (10), X11 is an electron-withdrawing group whose Hammett substituent constant "sgr"p is 0.20 or greater and preferably 0.30 or greater. The upper limit value of the constant is 1.0 for the electron-withdrawing group. Specific examples for X11 of an electron-withdrawing group whose Hammett substituent constant "sgr"p is 0.20 or greater are the same as those for X in the general formula (1); and preferences are also the same. Where X11 has a substituent, specific examples of the substituent are the same as those of X in the general formula (1); and preferences are also the same.
In the general formula (10), R11, R12, R13, R14, R15, R16 and Y11 each independently represents a hydrogen atom, a halogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, an aralkyl group, an aryl group, a heterocyclic group, a cyano group, a hydroxyl group, a nitro group, an amino group, an alkylamino group, an alkoxy group, an aryloxy group, an amido group, an arylamino group, a ureido group, a sulfamoylamino group, an alkylthio group, an arylthio group, an alkoxycarbonylamino group, a sulfonamide group, a carbamoyl group, a sulfamoyl group, a sulfonyl group, an alkoxycarbonyl group, a heterocyclicoxy group, an azo group, an acyloxy group, a carbamoyloxy group, a silyloxy group, an aryloxycarbonyl group, an aryloxycarbonylamino group, an imido group, a heterocyclicthio group, a sulfinyl group, a phosphoryl group, an acyl group, or an ionic hydrophilic group.
Among these groups, particularly preferable are a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a cyano group, an alkoxy group, an amido group, a ureido group, an alkoxycarbonylamino group, a sulfonamide group, a carbamoyl group, a sulfamoyl group, and an alkoxycarbonyl group.
The groups represented by R11 to R16 and Y11 have the same respective meanings as R3 to R6 in the general formula (1), and preferences are also the same.
In the general formula (10), R11 and R12, R13 and R11, and R15 and R12 may each form a ring. Where a ring is formed, preferable examples thereof are the same as the preferable examples of the rings that may be formed, respectively, by R1 and R2, R3 and R1, and R5 and R2 in the general formula (1).
In the general formula (10), A1, represents a group made up of nonmetallic atoms necessary for forming a 5- to 8-membered ring (the ring represented by A11 is hereinafter referred to as xe2x80x9cring A11xe2x80x9d upon occasion). The ring A11 may be a saturated ring or may have an unsaturated bond. Preferable examples of the group made up of nonmetallic atoms are groups made up of one kind, or two or more kinds, of the atoms selected from a nitrogen atom, an oxygen atom, a sulfur atom, and a carbon atom. The group made up of carbon atoms alone is particularly preferable.
Specific examples of the ring A11 are the same as those listed as examples of the ring A in the general formula (1) and preferences are also the same. Where the ring A11 has a substituent, examples of the substituent are the same as those listed as examples of the substituent that may be bonded by the ring A.
In the general formula (10), at least 3 of the nonmetallic atoms forming the ring All are substituted with the N atom of a pyrazole ring, Z11, and Z12, respectively, in such a manner that the atom substituted with the N atom of a pyrazole ring is adjacent to both the atom substituted with Z11 and the atom substituted with Z12.
The ring A11 is preferably a benzene ring. Particularly preferable is a benzene ring wherein, in addition to the N atom of the pyrazole ring, Z11 and Z12, the 4-position, in relation to the N atom of a pyrazole ring, is substituted with an ionic hydrophilic group (which may be substituted with the substituents described previously).
In the general formula (10), Z11 and Z12 each independently represents a halogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, an aralkyl group, an aryl group, a heterocyclic group, a cyano group, a hydroxyl group, a nitro group, an amino group, an alkylamino group, an alkoxy group, an aryloxy group, an amido group, an arylamino group, a ureido group, a sulfamoylamino group, an alkylthio group, an arylthio group, an alkoxycarbonylamino group, a sulfonamide group, a carbamoyl group, a sulfamoyl group, a sulfonyl group, an alkoxycarbonyl group, a heterocyclicoxy group, an azo group, an acyloxy group, a carbamoyloxy group, a silyloxy group, an aryloxycarbonyl group, an aryloxycarbonylamino group, an imido group, a heterocyclicthio group, a sulfinyl group, a phosphoryl group, an acyl group, or an ionic hydrophilic group.
Among these groups, a halogen atom, an alkyl group, an aryl group, a cyano group, an alkoxy group, an amido group, a ureido group, an alkoxycarbonylamino group, a sulfonamide group, a carbamoyl group, a sulfamoyl group, an alkoxycarbonyl group, and an ionic hydrophilic group are preferable; a halogen atom, an alkyl group, and an alkoxy group are particularly preferable; and a halogen atom is most preferable.
The groups represented by Z11 and Z12 have the same respective meanings as the groups represented by R11 to R16 and Y11, and preferences are also the same, except that Z11 and Z12 do not contain a hydrogen atom.
Among the azo dyes represented by the general formula (10), azo dyes represented by the following general formula (11) are preferable. 
In the general formula (11), X11, Y11, Z11, Z12, R11, R12, R13, R14, R15 and R16 have the same meanings as X11, Y11, Z11, Z12, R11, R12, R13, R14, R15 and R16 in the general formula (10), respectively. The same applies to the preferable examples of X11, Y11, Z11, Z12, R11, R12, R13, R14, R15 and R16.
In the general formula (11), Z13, Z14 and Z15 each independently represents a hydrogen atom, a halogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, an aralkyl group, an aryl group, a heterocyclic group, a cyano group, a hydroxyl group, a nitro group, an amino group, an alkylamino group, an alkoxy group, an aryloxy group, an amido group, an arylamino group, a ureido group, a sulfamoylamino group, an alkylthio group, an arylthio group, an alkoxycarbonylamino group, a sulfonamide group, a carbamoyl group, a sulfamoyl group, a sulfonyl group, an alkoxycarbonyl group, a heterocyclicoxy group, an azo group, an acyloxy group, a carbamoyloxy group, a silyloxy group, an aryloxycarbonyl, group, an aryloxycarbonylamino group, an imido group, a heterocyclicthio group, a sulfinyl group, a phosphoryl group, an acyl group, or an ionic hydrophilic group.
Among these groups, a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a cyano group, an alkoxy group, an amido group, a ureido group, an alkoxycarbonylamino group, a sulfonamide group, a carbamoyl group, a sulfamoyl group, an alkoxycarbonyl group, and an ionic hydrophilic group are particularly preferable.
Specific examples of Z13, Z14 and Z15 include the groups listed as specific examples of the substituents R1 to R6 and Y in the general formula (1).
Z13 and Z15 are more preferably a hydrogen atom, a halogen atom, or an alkyl group, and particularly preferably a hydrogen atom.
Z14 is preferably a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a cyano group, an alkoxy group, an amido group, a ureido group, a sulfonamide group, a carbamoyl group, a sulfamoyl group, an alkoxycarbonyl group, or an ionic hydrophilic group; more preferably a hydrogen atom, an alkyl group, or an ionic hydrophilic group; and most preferably an ionic hydrophilic group.
Of the azo dyes represented by the general formula (11) a particularly preferable combination of the substituents is as follows. X11 is a cyano group, an alkylsulfonyl group having 1 to 12 carbon atoms, or an arylsulfonyl group having 6 to 18 carbon atoms, and is particularly preferably a cyano group; Y11 is a hydrogen atom, an alkyl group, or an aryl group and is particularly preferably a hydrogen atom; R11 and R12 are each an alkyl group (which may have an ionic hydrophilic group as a substituent) or an aryl group (which may have an ionic hydrophilic group as a substituent); R13, R14, and R15 are each a hydrogen atom; R16 is an amido group (which may have an ionic hydrophilic group as a substituent); Z11 and Z12 are each a halogen atom or an alkyl group; Z13 and Z15 are each a hydrogen atom, a halogen atom, or an alkyl group and is particularly preferably a hydrogen atom; and Z14 is a hydrogen atom, a halogen atom, a sulfonamide group, a carbamoyl group, a sulfamoyl group, an alkoxycarbonyl group, or an ionic hydrophilic group, and is particularly preferably an ionic hydrophilic group.
A preferable combination of substituents of a compound represented by the general formula (11) is as follows. A compound in which at least one substituent among various substituents of the compound is one of the preferable group described above is preferable, a compound in which more substituents thereof are the preferable groups described above is more preferable, and the compound in which all substituents thereof are the preferable groups described above is most preferable.
However, it is necessary that, in the general formula (10), at least one of R11, R12, R13, R14, R15, R16, X11, Y11, Z11, Z12, and A11 represents an ionic hydrophilic group or has an ionic hydrophilic group as a substituent, and that, in the general formula (11), at least one of R11, R12, R13, R14, R15, R16, X11, Y11, Z1, Z2, Z3, Z4, and Z5 represents an ionic hydrophilic group or has an ionic hydrophilic group as a substituent. Because the azo dye represented by the general formula (10) or by the general formula (11) has in the molecule thereof at least one ionic hydrophilic group, solubility or dispersibility in an aqueous medium is good. Ionic hydrophilic groups as substituents of R11 to R16, X11, Y11, and Z11 to Z15 include a sulfo group, a carboxyl group, and a quaternary ammonium group. Among these groups, a sulfo group and a carboxyl group are preferable, and a sulfo group is particularly preferable. The carboxyl group and the sulfo group may each be in a state of a salt. Examples of a counter ion that forms the salt include alkali metal ions (e.g., a sodium ion or a potassium ion) and organic cations (e.g., a tetramethylguanidinium ion).
The azo dyes represented by the general formula (11) are more preferably the azo dyes having the structures represented by following general formula (12). 
In the general formula (12), X11, Y11, Z11, Z12, Z14, R11, R12 and R16 have the same respective meanings as X11, Y11, Z11, Z12, Z14, R11, R12 and R16 in the general formula (11). The same applies to preferable examples of X11, Y11, Z11, Z12, Z14, R11, R12 and R16.
Of the azo dyes represented by the general formula (12), a particularly preferable combination of the substituents is as follows. X11 is a cyano group, an alkylsulfonyl group having 1 to 12 carbon atoms, or an arylsulfonyl group having 6 to 18 carbon atoms, and is particularly preferably a cyano group; Y11 is a hydrogen atom, an alkyl group, or an aryl group and is particularly preferably a hydrogen atom; R11 and/or R12 is an alkyl group (which may have an ionic hydrophilic group as a substituent) or an aryl group (which may have an ionic hydrophilic group as a substituent); R16 is an amido group (which may have an ionic hydrophilic group as a substituent); Z11 and/or Z12 is a halogen atom or an alkyl group; and Z14 is a hydrogen atom, a halogen atom, a sulfonamide group, a carbamoyl group, a sulfamoyl group, an alkoxycarbonyl group, or an ionic hydrophilic group, and is particularly preferably an ionic hydrophilic group.
A preferable combination of substituents of a compound represented by the general formula (12) is as follows. A compound in which at least one substituent among the various substituents of the compound is one of the preferable groups described above is preferable, a compound in which more substituents thereof are the preferable groups described above is more preferable, and a compound in which all substituents thereof are the preferable groups described above is most preferable.
Details of azo dyes which are represented by a general formula (13) and which are particularly preferable among the azo dyes represented by the general formula (11) are given below. The compounds, which are represented by the general formula (13) are useful as water-soluble dyes for ink-jet printing ink and also as synthetic intermediate products of water-soluble dyes. The compounds can also be useful intermediates for chemical products, drugs, or agricultural chemicals. 
In the general formula (13), X11, Y11, Z11, Z12, Z13, Z14, Z15, R11, R12, R13, R14, R15, and R16 have the same respective meanings as X11, Y11, Z11, Z12, Z13, Z14, Z15, R11, R12, R13, R14, R15, and R16 in the general formula (11). The same applies to preferable examples of X11, Y11, Z11, Z12, Z13, Z14, Z15, R11, R12, R13, R14, R15, and R16.
Among the azo dyes represented by the general formula (13), particularly preferable combinations of substituents are the same as the particularly preferable combinations of the substituents for the general formula (11).
A preferable combination of substituents of a compound represented by the general formula (13) is as follows. A compound in which at least one substituent among the various substituents thereof is one of the preferable groups described above is preferable, a compound in which more substituents thereof are the preferable groups described above is more preferable, and a compound in which all substituents thereof are the preferable groups described above is most preferable.
However, it is essential that, in the general formula (13), at least one of R11, R12, R13, R14, R15, R16, X11, Y11, Z11, Z12, Z13, Z14, and Z15 represents an ionic hydrophilic group or has an ionic hydrophilic group as a substituent. Because the azo dye represented by the general formula (13) has in the molecule thereof at least one ionic hydrophilic group, solubility or dispersibility in an aqueous medium is good. Ionic hydrophilic groups as the substituents of R11 to R16, X11, Y11, and Z11 to Z15 include a sulfo group, a carboxyl group, and a quaternary ammonium group, of these groups, a sulfo group and a carboxyl group are preferable, and a sulfo group is particularly preferable. The carboxyl group and the sulfo group may each be in a state of a salt. Examples of the counter ion that forms the salt include alkali metal ions (e.g., a sodium ion or a potassium ion) and organic cations (e.g., a tetramethylguanidinium ion).
The azo dyes represented by the general formula (13) are more preferably azo dyes having structures represented by a following general formula (14). 
In the general formula (14), X11, Y11, Z11, Z12, Z14, R11, R12 and R16 have the same respective meanings as X11, Y11, Z11, Z12, Z14, R11, R12 and R16 in the general formula (12). The same applies to preferable examples of X11, Y11, Z11, Z12, Z14, R11, R12 and R16.
In the azo dyes represented by the general formula (14) particularly preferable combinations of substituents are the same as the particularly preferable combinations of substituents in the general formula (12). However, it is essential that at least one of the substituents represents an ionic hydrophilic group or has an ionic hydrophilic group as a substituent.
A preferable combination of substituents of a compound represented by the general formula (14) is as follows. A compound in which at least one substituent among various substituents is one of the preferable group described above is preferable, a compound in which more substituents thereof are the preferable groups described above is more preferable, and a compound in which all the substituents are the preferable groups described above is most preferable.
Specific examples (indicated as exemplary compounds 101 to 143) of the azo dyes represented by the general formulae (10) to (14) are given below. However, it should be noted that the azo dyes to be used in the present invention are not limited to these examples. 
The compound represented by the general formula (10) is characterized in that substituents Z11 and Z12, each larger than a hydrogen atom, are present on the ring A11 (in particular, on the atom adjacent to the atom substituted with the N atom of the pyrazole ring). Because of this, the plane of the pyrazole and the plane of the ring A11 are twisted out of the same plane. This structure is thought to result in a marked improvement of hue and lightfastness. The improvement of the hue and lightfastness brought about by this characteristic structure cannot be anticipated from the prior art described previously.
The azo dyes represented by the general formula (10) or the general formula (11) can be synthesized by a diazo coupling reaction between a coupling component, i.e., an aniline derivative represented by one of following general formulas (i) and (iii), and a diazo component, i.e., a heterocyclic amine (5-amino-pyrazole) represented by one of following general formulas (ii) and (iv). 
In preparation of a diazonium salt of the heterocyclic amine derivative (5-amino-pyrazole), an organic solvent can be used as a reaction solvent (e.g., an aliphatic acid-based solvent such as acetic acid, propionic acid, or isobutyric acid; an alcoholic solvent such as methanol, ethanol, or isopropyl alcohol; an amide-based solvent such as N,N-dimethylacetamide, N,N-dimethylformamide, or 1-methyl-2-pyrrolidone; sulfolane-based solvent such as sulfolane; a sulfoxide-based solvent such as dimethyl sulfoxide; a ureido-based solvent such as tetramethylurea; a halide-based solvent such as dichloromethane, chloroform, or 1,2-dichloroethane; an ester-based solvent such as ethyl acetate and butyl acetate; or an ether-based solvent such as diethyl ether or tetrahydrofuran). These organic solvents can be used singly or as a mixture of two or more. Further, a mixture of an organic solvent and water can be used. Furthermore, water as a single solvent can be used, of these solvents, an aliphatic acid-based solvent, an ester-based solvent, or an ether-based solvent are preferable. Mixtures of these solvents with alcoholic solvents or water are also preferable. The most preferable solvents are a single organic solvent, i.e., an aliphatic acid-based solvent or an ester-based solvent, a mixture of the same with water, or water as a single solvent.
Examples of the acid that can be used include hydrochloric acid, nitric acid, sulfuric acid, methanesulfonic acid, trifluoromethanesulfonic acid, heptadecafluorooctanesulfonic acid, acetic acid, trifluoroacetic acid, propionic acid, and mixtures of these acids. Among these acids, sulfuric acid, trifluoromethanesulfonic acid, and heptadecafluorooctane sulfonic acid are preferable. Sulfuric acid and heptadecafluorooctanesulfonic acid are particularly preferable.
Examples of the diazotizing agent that can be used include sodium nitrite, an aqueous sodium nitrite solution, potassium nitrite, an aqueous potassium nitrite solution, isoamyl nitrite, and nitrosyl sulfate (a sulfuric acid solution). Among these diazotizing agents, the aqueous sodium nitrite solution, isoamyl nitrite, and nitrosyl sulfuric acid (a sulfuric acid solution) are preferable. The use of isoamyl nitrite or nitrosyl sulfuric acid (sulfuric acid solution) as the diazotizing agent is particularly preferable.
The reaction temperature is within the range of xe2x88x9278 to 50xc2x0 C., preferably within the range of xe2x88x9220 to 20xc2x0 C., and most preferably within the range of xe2x88x9220 to 10xc2x0 C.
Examples of a solvent that can be used as a reaction solvent in a diazo coupling reaction (i.e., conversion into an azo dye) include organic solvents such as an aliphatic acid-based solvent such as acetic acid, propionic acid, or isobutyric acid; an alcoholic solvent such as methanol, ethanol, or isopropyl alcohol; an amide-based solvent such as N,N-dimethylacetamide, N,N-dimethylformamide, or 1-methyl-2-pyrolidone; a sulfolane-based solvent such as sulfolane; a sulfoxide-based solvent such as dimethyl sulfoxide; a ureido-based solvent such as tetramethylurea; a halide-based solvent such as dichloromethane, chloroform, or 1,2-dichloroethane; an ester-based solvent such as ethyl acetate or butyl acetate; an ether-based solvent such as diethyl ether or tetrahydrofuran, and a pyridine-based solvent such as pyridine, xcex1-picoline, or 2,6-lutidine. These organic solvents can be used singly or as a mixture of two or more. Further, a mixture of an organic solvent and water can be used. Furthermore, water as a single solvent can be used. Of these solvents, an aliphatic acid-based solvent, an amide-based solvent, an ester-based solvent, and an ether-based solvent are preferable. Mixtures of these solvents with alcoholic solvents or water are also preferable. The most preferable solvents are a single organic solvent, i.e., an aliphatic acid-based solvent or an amide-based solvent, or a mixture of the same with an alcoholic solvent or water.
Examples of the base that can be used include organic bases (e.g., an aliphatic amine such as a triethylamine aqueous solution, triethylamine, tripropylamine, diisopropylethylamine, triethanolamine, or diethanolethylamine; an aromatic amine such as N,N-dimethylaniline or N,N-diethylaniline; or a nitrogen-containing unsaturated heterocycle such as pyridine, xcex1-picoline, 2,6-lutidine, pyridazine, or N-imidazole) and inorganic bases (e.g., an acetate such as potassium acetate or sodium acetate; a carbonate such as potassium carbonate, sodium carbonate, sodium hydrogencarbonate, or potassium hydrogencarbonate; or a metal hydroxide such as sodium hydroxide or potassium hydroxide). Of these bases, aliphatic amines, nitrogen-containing unsaturated heterocycles, and acetates are preferable. The most preferable bases are aliphatic amines and acetates.
The reaction temperature is within the range of xe2x88x9278 to 50xc2x0 C., preferably within the range of xe2x88x9220 to 20xc2x0 C., and most preferably within the range of xe2x88x9220 to 15xc2x0 C.
The product obtained by these reactions is post-treated according to ordinary methods employed in organic synthesis and is used after being purified or without being purified. That is, the reaction product which comprise materials liberated from the reaction system may be used without purification. Otherwise, the reaction product which comprise materials liberated from the reaction system may be subjected to a single operation or a combination of operations such as recrystallization, column chromatography, and the like. Alternatively, after completion of the reactions, the reaction product, after removal of the reaction solvent by distillation or without removal of the reaction solvent, is poured into water or ice water. After that, the reaction product which comprise materials liberated from the reaction system, after being neutralized or without being neutralized, may be used without purification or subjected to a single operation or a combination of operations comprising such as recrystallization, column chromatography, and the like. Further alternatively, after the completion of the reactions, the reaction product, after removal of the reaction solvent by distillation or without removal of the reaction solvent, is poured into water or ice water. After that, the resulting mixture, after being neutralized or without being neutralized, may be extracted with an organic solvent. This extract may be used without being purified, or the extract maybe subjected to a single operation or a combination of operations such as crystallization, column chromatography, and the like.
Specific examples of the synthesis of the pyrazolylaniline azo dye derivatives of the present invention are given below. In the preparation of the azo dye derivatives of the present invention, the synthesis intermediates, namely, a compound (C) which is a heterocyclic amine derivative and compounds (E) and (F) which are aniline derivatives, were synthesized according to the following synthesis routes as intermediates of exemplary compounds. Subsequently, the exemplary compounds (101) and (103) were synthesized according to the diazo coupling reaction described above. 